Key-action.



PATENTED MAY 5, 1908.

J. G. WAHL.

KEY ACTION.

APPLICATION FILED AUG. 1.1907.

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" J. 0. WAHL.

KEY AOTION.

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wax/M5565. 2720672507" UNITED sures-PATENT orrrcn JOIIN O. WAHL, OF CHICAGO, ILLINOIS.

KEY-ACTION.

Specification of Letters Patent.

Patented May 5, 1908.

Application filed August 1, 1907. Serial No. 336,504.-

. To dll tohom'it may concern:

Be it known that I, JOHN C. WAHL, citizen of the United Statesresiding at Chicago, in

keys, there is apt to be non-uniformity in the appearance-of the printing on the paper. If a ight fingered person manipulates thekeys, the printing is apt to be more or less faint, whileif a heavy fingered person strikes the keys, the printing is veryheavy and perhaps the paper is cut by the type.

The main object -of my invention, there,-

fore, is toprovide improved action mechanism intervening'between the/keys and the type, which mechanism will automatically cause the type to strike the platen with uniformf orce independent of the pressure or forceexerted upon thekeys. In typewriting machines, for instance, in the well known Remington typewriting .machines', the type bars or rods are connected directly with the key levers so that the pivoted bars carrying the type are thrown against the platen with a force dependent upon the. force with which the keys are'struck. Instead of having this direct connection, Iinterpose a spring mechanism between the type rods and the key bars which spring mechanism is primarily actuated upon depression of the keys Without causing movement of the type rods, but

which mechanism tripped. after the key has been depressed so that the force of the spring alone will cause the typebar and type to be thrown against the-platemand no matter what the force ,GXGI'tBd on the keys may be, the'force which. throws the type against the platen is produced by the spring mechan-;

ism, and-the springmechanisms are made uniform. for the various keys, so that the printing will all be uniform and of equal strength. The tripping mechanism is also associated with the escapement mechanism of the typewriter: carriage, adjustment beings'uchthat tripping. takes lace to cause t e'trr t9 ya i e h a n ete. the

capement mechanism may operate to allow the carriage to escapei My invention will be clearly understood when described with reference to the 'accom panying drawings in which Figure 1 is a more or less diagrammatic view, showing part of a typewriter frame and the arrangement for one key, the equipment being the same for each key, Fig. 2 shows a modified arrangement of driving mechanism for a calculating attachment which may be applied to -the.typewriter.

1 represents, the base of the frame of the well known Remington typewritingmachine.

from which extend, the uprights 2, 2, supporting the table or top plate 3. "The escape- 'ment carriage body 4 travels on the track 5,

and the rotatable front part of thecarriage '6 carrying the platen roller 7 rests. on the track 8, as is well known.

9 shows a keybar having at itsfrontend the finger plate 10, being pivoted at its rear end 11 'in'the pivot case 12 ofthe typewriter frame.

13 shows'a type rod adjustably connected with the coupling inem'oer 14. The upper end of this type-rod connects with the arm 15- f of the bell crank-shaped type bar 16 ivoted at 17 and which carries at its end the type block 18 The centers of the pivot 17 and ofthe platen roller 7 are a distance apart so that the type blocks of the various type bars which are spaced about the platen, will all strike the platen at a certain central point, as is well known. In the Remington and other machines now on the market, the coupling members 14 are connected directly with the keybar g, and when a key is struck the type block Will-strike the platen with a force in proportion to the force with which the key is struck.

According to my invention, the connection between the ty e levers and the key bars is not direct, but interpose mechanism which will cause the type blocks to all strike the platen with uniform force. This intermediary mechanism comprises a plurality of levers 18 pivoted to a shaft 19 supported in the bearings 20 mounted on the pivot case 12,

and the, front endof each lever is connected with the coupling member 14 of the corre- .type lever mechanism. To the spondi rear of t e connection of each lever with the .coi1pling 14, the lever has a slot 21 inwhich hooked d 22 v pling member 23 having adjustable engagement with a companion coupling member 24 which is pivoted to a corresponding key bar 9. Also connected between the lever 18 and the key bar 9 is a tension spring 25. A tongue 26 extends downwardly from the lever 18 and provides a stop shoulder 27 which norumally 'engages the stop or tripping bar 28 nected between this rotatable frame and the machine frame serves to normally hold the tripping bar'28 against the tongues 26 and under the shoulders 27 of the various levers 18. Upon depression of a key, therefore,

there can be no corresponding movement of the lever: 18 and of the typewriter mechanism as long-as the bar 28 is belowthe shoulder 27 of the struck key, but the spring 25 will be extended and a downward pull exerted upon the lever 18. Mechanisms,however, are provided for rotating the shaft 30 and therewith the arms 29 to withdraw the shaft 28 from, the shoulder 27, and the spring 25 will then shut and will pull down the lever 18, consequently, causing rotati n of the type bars 16 andengagement of the type block 18 with the platen, the force with which the type bar strikes the platen being determined by the strength of the spring 25, and the springs for the various keys may all be of equal strength, so that the ty e bars will all strike with uniform force. o lessen the friction, the shaft 28 may be provided with a roller 32.

The mechanism for rotatin shaft '30 and for tripping levers 18 maybe 0 variousforms. As shown, a pivot shaft 33 maybe pivoted between the front supporting posts 2 of the machine frame from which shaft extend the arms 34 and 35.- The arm 35connects through rod 36 with the escapement bar 37, arrangedbelow the key bars 9' of the machine in a well known manner, this bar being struck by the key bars after theyhavebeen actuated sufficiently to cause the type bars.

controlled thereby to strike the platen. The arm 35 extends horizontally, and the arm 34 extends vertically downward, and from the end of the arm 34 I have shown a bar 38 extending rearwardly and connecting with the arm 39 of the bell crank lever 40 pivoted at the end of the arm 41 extending forwardly from the casing 12. The other arm 42 of this bell crank lever is connected to a rod 43 which extends u wardly and which is connected with the ell crank lever mechanism allows anescapem'ent of the paper carria e.- On the rod 38 is secured the block 48 as y means of a set screw 49, and extending upwardly from the shaft 30 is a pin 50.

The operation of the mechanism thus far described is as follows: Upon depression of the key, the spring 25 is extended, the lever 18 remaining stationary as the tripping bar 28 is below the shoulder 27. When the key reaches the escapement bar 37 and depresses said bar, the arm 35 will be swung to rotate shaft 33 and to swing arm 34 forwardly, thereby drawin bar 38 forwardly and caus ing rotation'of t e bell crank lever 40. However, before the escapement mechanism connected with the lever 40 can be actuated sufficiently to release the paper carriage, the' block 48 will engage the pin -50 to rotate be tripped before the hooked end engages the lower end of the slot, and the hooked end then mainly serves the purpose of checking or limiting the downward travel of the bar 18, when the bar is tripped; The force of the spring 25, therefore, absolutely controls the force with which the type bar strikes the platen, and no matter how lightly-0r how heavily the key is struck, the printing ofthe type will be uniform.

Calculating attachments are also being provided for typewriting machines, which attachments are directly connected with the number keys of the machine, as shown, for example, in my copending applications. On the drawings 1 havediagrammatically represented such calculating mechanismby the reference character 51 which calculating mechanism is shown connected with the paer carriage part 4 by meansv of the connecting bar 52. This calculating mechanism or totalizer mechanism has the totalizer gear wheels represented by 53, which are adapted for engagement with the intermediary gearmechanism 58 connects each gear frame 55. with the corresponding key bar 9 so that upon depression of the key, the gear frame 55 is rotated, and the gearing mechanism 54 inthe lever 18 is such that the lever 18 will to the rear 'of these extensions isa bar 60 pivoted at its endsin the machine frame.

tending-from this bar is the cam web 61'to be' engaged by the cam extensions 59 upon rotation of a'gear frame 55. lever 62 extends upwardly'from the bar-60 and is connected through link 63 with the upper end of the arm 64 extending upwardly from shaft 33. When 'a key is depressed, the gear frame 55 connected therewith through the coupling mechanism 58' is rotated, and its gear teeth 57 causes a rotation of the intermediate gearing mechanism 54 and the engaged totalizer ear 53 'correspondingto the number of the ey depressed. The bar 60 is also rotated by the cam extension 59, and its motion transmitt'ed through lever 62, link- 63, arm 64, shaft-33, arm 34,'bar 38 and block 48 to the pin 50 to cause rotation of the tripping frame and operation of the lever 18 by'the spring to cause the type bar'to strike the platen and to print the number corresponding to the depressed key. The'movement' of the bar 38 also rotates the bell crank lever40 and thereby causes actuation of the escapement mechanism to allow escape of the pa er carriage: The lostunotion between the b 00k 48 and pin 50fand;the"adjustments of the various levermechani'smsand cam extension engagements issuchtha-t the totalizer mechanism the platen.

action will have been completed before the tripping frame is actuated to allow operation of the type bar, and the e'scapement meehan ism isa'ctuate'dafter the type bar has struck When this arrangeme'nt is used,

' the adjustment is also such that the tripping of'the type mechanism and operation of the escapement mechanism is independent of the escapement bar 37 the operations taking place before the key lever 9 engages the escapement bar. Accurate and-complete operation of the totalizer or calculating mechanism is, therefore, accomplished and assured beforethe result is printed and before the paper carriage is allowed to escape.

In Fig. 2 is shownla modified arrangement for causing operation of the type and escapement mechanism. In Fig. 1 the link 63 gives a positive and rigid connection between the arms 62 and 64, and the shaft 33 begins to rotate almost immediately upon deprsssion of the key, but is not rotated far enough to cause action of the type mechanism or escapement mechanism until the calculation has been performed. In Fig. 2, however, a yielding .connection is afforded between the arms 62 and 64, the link 63 having a slot 65 engaged by the pin 66 extending from arm 62, and a spring 67 connects this pin with the pivot point 68 which connects the other end of the link 63 with arm 64. With this arrangement when the key is struck, the shaft 33 will not be rotated immediately, but the spring 67 will be extended upon rotation of the bar, 60, and when the gear frame has been rotated sufiiciently to cause complete actuation of the calculating mechanism, the'pin 66 will engagethe end of slot 65 and start rotation of the shaft 33 whose rotation will-then be completed by the force of the closing s ring 67 and the trippingmechanism, and then the escapement mechanism will be actuated prom tly. -Ihis arrangement is'perhaps more re iable than that shown in Fig. 1 which is inclinedto be more or less sluggish in its operation.

My invention thus described renders the printin of the type entirely independent of -the stri ingforce on the keys, the printing of the type bars, being at all-times uniform. If lighter 'or heavier printing is desired, adjustment can easilybe made by changing the force of the springs 25..

I do not Wish to be limited'to the exact 'arrangements which I have shown, as changes may readily be made within the scope of my invention, the main and broad feature being themeans for causing the uniform striking and printing of thetype.

I desire tosecure' the following claims'by Letters Patent:

1. In a-machine of the class described, the combination of keys, typebars, spring mechanism connecting each type bar with one of the keys, and mechanism for preventing 'operation of the type bars by the spring mec anism upon' actuation of a key until said key has been actuated a redetermineddistance. 2. In a machine of the classdescribed, the combination "of a key, a type bar, and elastic connection between the type bar and the key, and meansforpreventing operation of the type bar by the elastic connection until the key has been actuated a predetermined distance.

3. In a machine of the class described, the combination of a key, a type bar, elastic connecting mechanism between the 'key and the type bar, means for storing energy in the elastic connecting mechanism u on actuation of the key, and means for a lowing actuation of the type bar by the stored-up energy and the elastic connecting mechanism when the key has been actuated a predetermined distance.

4. In a machine of the class described, the combination of a key, a type bar, energystoring means connected with the type bar, means for storing energy in the energy-storing means upon actuation of the key, and means for allowing the stored energyto operate the type bar after an interval of actuation of the key.

5. In a machine of the class described, the combination of a key, a type bar, and elastic mechanism connected with the key and with the type bar for determining the operation 0 of the type bar independently of the key action. p

6; In-a machine of the class described, the combination of a key, a type bar, and elastic mechanism intervening between the key and the type bar, said elastic mechanism being energized upon actuation of the key, and then allowed to direct its accumulated energy to operate the type bar.

7. In a machine of the class described, the combination of a key, a type bar, elastic mechanism betweenthe key and the type bar, actuation of the key causing storing of energy in the elastic mechanism, means for preventing movement of the type bar during the storing of energy in the elastic mechans ism, and means for subsequently allowing the stored energy in the elastic mechanism to operate the type bar. I

. 8. In a machine of the class described, the combination of a key, a type bar, an elastic member connecting the key with the type bar, actuation of the key causing storing of energy in the elastic member, tripping mechanism for preventing movement of the type bar during such storing of energy, and means foractuating the tripping mechanism to allow'the elastic member to direct its stored energy toward operating the type bar.

=9. Ina machine of the class described, the combination'of a key, a type bar, an elastic member connecting the type bar with the key, tripping mechanism for normally preventing movement of the type bar, actuation of the key' causing operation of. the elastic member whereupon energv is'stored therein, and means controlled by the movement tr the key for actuating the tripping mechanism to release the type bar whereby the energy stored inthe elastic member becomes eifective to operate the type bar.

10. In a machine of the class described,

the combination of a key, a type bar, a spring connecting the key withthe type bar, tripping mechanism normally having engagement with the type bar to prevent operation bar is held by the tripping mechanism, and

means for actuating the tripping mechanism to allow the energy'in the spring to operate the ty e bar. 1

11. In a machine of the class described, the combination of a key, a type bar, a spring connecting the key with the type bar, tripping mechanism normally having engage ment with the type'bar to prevent operation thereof, actuation of the key causing the storing of energy in the spring while the type bar is held by the tripping mechanism, and means controlled by the movement of the key for actuating the tri ping mechanism to allow the type bar to be operated by the energy stored in the spring.

12. Ina machine of the class described, the combination of a key, a type bar, and elastic connecting mechanism between the keyand thetype-bar for determining the force with whichthe type bar is operated in-' dependently of the force with which the key is actuated.

13. In a machine of the class described,

the combination of a key, a type bar, and

be struck into uniform force for actuating the type bars. In witness whereof, I hereunto subscribe my name this 9th day of July A. D., 1907.

JOHN C. 'WAHL.

Witnesses:

CHARLES J. SCHMIDT, LEONARD W. NOVANDER. 

